Can an off duty police officer step out in the middle of the street and stop me?

So I was driving with my friends, and I was in a neighborhood. I live in Indianapolis, IN also. I pretty much didn't stop all the way for a stop sign, then I drove up a hill. When I came back down, this guy coming out of his house stopped me in the middle of the street and took me to the side. He asked me for my Drivers License and asked me a bunch of questions. He addressed no authorization besides when he said "didn't know you blew threw a stop sign by a cops house did u?" I gave him my license and answered his questions. Would he have had the right to write me a ticket and did he have the right to stop me and demand answers from me and all that? What questions didn't I have to answer?